February 2012 Archives

If you think arsenic poisoning is something relegated to the pages of mystery novels, think again. Arsenic may be in foods you routinely eat—but it's undetectable by taste or smell. How much arsenic in your diet is safe?

Number 33 on the periodic table, arsenic is a naturally-occurring heavy metal—and a much-used poison throughout history. Because it appears in the soil, arsenic may be lingering in foods you and your family frequently eat. Recent research raises questions about arsenic levels in rice products, apple juices, and pear juices. Image source: Wikipedia.

When I spotted a headline in my Facebook stream a few weeks ago that warned of arsenic in food products made with rice, or sweetened with brown rice syrup, I was curious. The NPR headline wasn't alarmist. It was, instead, middle of the road: "Yes, There's Arsenic In Your Rice. But Is That Bad?"

I didn't know it then, but apparently I had missed out on public alarm over similar headline news (and FDA response) last year about arsenic levels in apple juice. The idiom "what you don't know can't hurt you, right?" comes to mind as particularly foolhardy when it comes to health consciousness, and catching wind of potentially dangerous levels of 'poison' in my rice wasn't a comfortable thought. From the indulgence of a comfort food like rice pudding to my favorite short-grain brown rice, good with just about everything (including milk and sugar), to a frequent menu of ethnic foods, often accompanied by rice, the grain has earned 'staple' classification in my vegetarian diet. And, while my kids haven't wholeheartedly jumped on the bean and spinach train of my healthy eating, "rice" is something they've grudgingly adopted as a frequent side dish and part of my attempt to incorporate more whole grains in their diets.

My health-consciousness hackles already raised, as I read the initial report, I got even more icky feeling when I saw that the levels of arsenic in brown rice are reportedly higher, on average, than in the ostensibly less-good-for-you white counterpart.Great, I thought. Here's another instance where many of us have made lifestyle eating changes in the name of whole grain and better health, and suddenly we find out that what we did with the best of intentions can actually be causing unexpected (and unseen) harm.

Further reading told me that while the FDA has established guidelines for the acceptable threshold of arsenic in bottled drinking water, there are no regulations in place for food products—or beverages other than water. I'd read enough. In what has become my typical modus operandi since I began working at Science Buddies, I fired off an email to our Lead Scientist. In part, I wanted to know what a student could do to explore this issue. In part, I wanted her opinion of the issue and the potential health risk.

It was from her response that I realized I'd somehow overlooked the rampant apple juice reports last year. Her response clued me in to the larger spiral of arsenic concern but also gave me the kind of "slow down, be objective, and understand the facts" counsel which you might expect from a scientist. In other words, she put the 'headline' in perspective: Arsenic is in our food chain.

A Dark History

Mystery reader or not, most of us are familiar with the classic whodunit plot that involves poisoning by arsenic. Agatha Christie favored arsenic in her mysteries, along with a host of other poisons, strychnine being the most common, but "Arsenic and Old Lace" may be one of the most famous of arsenic-laden storylines. At the heart of the tale are "two spinster aunts who have taken to murdering lonely old men by poisoning them with a glass of home-made elderberry wine laced with arsenic, strychnine, and 'just a pinch' of cyanide" (Wikipedia).

With arsenic having a prominent and deadly role in such stories, I started looking at arsenic more broadly, trying to make sense of the fact that a known poison was also part of last night's dinner, which I cooked for myself. As I started down the research path before me, a path scattered with arsenic-laced grains of brown rice, I quickly realized that arsenic has a fascinating history, one that gets increasingly insidious, dark, and creepy the farther you look, from its use as a rat poison to its, ostensibly well-earned, nickname, "the inheritance powder."

Digging into the history of arsenic as a choice for mystery writers leads to interesting facts about the availability and early uses of arsenic, and a scan of a list of historical poisonings (alleged and confirmed) shows arsenic popping up a fair number of times. Perusing the Wikipedia entry on arsenic poisoning brings other well-known historical figures to the forefront as possible victims of the secret poison, including Napoleon Bonaparte.

And then, of course, there was Mary Ann Cotton, convicted in 1873 of murdering more than 20 people, including her children, with arsenic. Though not a household name in the way other serial killers have occupied public consciousness, Cotton's tale is frightening and might make you think twice about accepting a drink (or a rice ball) from a friend! One of the most unexpected finds in my jaunt through the history of arsenic poisoning was an article from November 2011 covering a current mystery writer's speculation that Jane Austen, whose cause of death at age 41 remains the subject of much conjecture, may have died of arsenic poisoning.

Hidden Ingredients

Given the history of arsenic and its association with "secret" poisoning, it's certainly discomfiting to realize that arsenic isn't something confined to the intrigues of centuries gone by or the dark and dusty upper recesses of a mystery book protagonist's kitchen cabinets. Instead, arsenic, in trace amounts, may well be sitting on the shelves of many of our cabinets and most of our grocery stores.

In reality, arsenic is a naturally-occurring element in the Earth's crust, number 33 (Arsenum) on the periodic table. From arsenic released by volcanoes to arsenic produced as a byproduct of burning fossil fuels, arsenic, in both its organic and inorganic forms, appears worldwide. Studies have shown that animals even need a trace amount of arsenic in their diets. Whether humans also need a bit of arsenic—and how much—has yet to be conclusively determined.

Why Rice?

Part of the problem is that the soil rice is grown in may contain arsenic, both natural and residual, and rice may absorb arsenic more easily than other foods. As for the difference in arsenic levels between brown and white rice, a report in the MinnNews suggests that processing rice may remove some of the inherent arsenic: "The arsenic accumulates in the rice's outer hull and stays there unless the hull is removed (as it is during the processing of white rice)."

While studies are relating the amount of arsenic detected in brown-rice syrup to the limits of arsenic allowed by the FDA in drinking water, whether or not the same thresholds can be considered safe in food has not been determined. Reports, however, like this one in USA Today from December 2011, suggest that even 1/2 a cup of rice a day, may provide too much arsenic for health safety.

So arsenic surrounds us. It is, as I was warned, a part of our food chain. Even so, arsenic in certain levels is toxic—and arsenic is a known, but undetectable to the consumer, factor in certain foods. In other words, you don't have to be someone's victim to be ingesting a known poison. Think about how many foods are rice-based. Cereals, salads, puddings, and even snacks may be made from rice or contain brown-rice syrup, commonly used as a sweetener. Rice cake anyone? Energy bar? If rice contains arsenic, and it doesn't have to be monitored or regulated, it seems to me we have a problem. Checking ingredients labels won't help. "Arsenic" hasn't been "added." Complicating matters is the fact that not all brown rice or brown rice syrup contain the same levels of arsenic, a reality that seems to beg the question: why isn't it being regulated?

Making Connections

Unfortunately, arsenic detection isn't something students can tackle at home or in a kitchen-based lab. But students can look at the larger picture and take into account that arsenic is a heavy metal, a class that also contains silver, copper, mercury, nickel, cadmium, and chromium, all of which can be toxic in certain environments. The Heavy Metals and Aquatic Environments project lets students investigate the impact of the heavy metal copper (Cu) on an aquatic environment containing snails and plants.

While students can't evaluate the relationship of arsenic and rice—or the impact of arsenic on human biology—as easily, a firsthand investigation of heavy metals and the consequences of increased levels, and of buildup, can help students better understand the unfolding news and research related to arsenic.

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A student's investigation into biofuel finds support and mentorship in the Science Buddies Ask an Expert forums.

Assistance from a Bio-Rad Expert helped fuel Naima's interest in environmental science and led to a successful advanced science investigation. To read about other inspiring student and teacher science project successes, visit the Science Buddies in Action page!

Summary

Having utilized Science Buddies resources in previous years, Naima Raza was no stranger to science fairs or to Science Buddies when she consulted Experts in the Ask an Expert forum about her 8th grade environmental science project. With the assistance of an Expert from Bio-Rad Laboratories, Naima turned her interest in biofuels into an award-winning project.

Overview

For Naima, Science Buddies resources, Project Ideas, and Ask an Expert forums have proven both inspirational and invaluable as she has prepared, designed, and executed school science projects over the last several years. Before working on her environmental science project for her 8th grade science fair, Naima had already conducted two science fair projects on environmental science topics, starting with a project in the 6th grade on solar desalination of saltwater. At the time, Naima found the idea that the sun alone could turn salt water into fresh water fascinating. "That the process could also be applied to helping solve a widespread world issue was even more significant," recalls Naima. "I was sincerely interested in making a difference and helping the world become a better place."

That sentiment has continued to guide Naima's research and interest in science. In the 7th grade, she explored the role of substrates in microbial fuel cells. When asked "why" she thinks it is important for students to tackle environmental science questions, her answer is immediate and simple: "Working on environmental science projects is logical!"

"Everybody knows the rapid and dangerous change that the world is going through, and we are already seeing the harmful effects," says Naima. "How can we disregard this issue so easily? The environment affects everything! For example, environmental changes such as climate change are creating and spreading new diseases and making humans even more vulnerable to common diseases. If we can first focus on making our Earth more sustainable, then I'm sure that solving other issues will become easier."

Science Buddies Offers Inspiration and Guidance

Naima's 6th and 7th grade science projects were both inspired by Science Buddies Project Ideas. For each project, she adapted a Science Buddies idea to address her own questions, resulting in a custom experiment each year. When it was time to begin her 8th grade project, Naima returned to Science Buddies and to the Ask an Expert forums where she had received past assistance from volunteer Expert Donna Hardy of Bio-Rad Laboratories. As Naima considered her 8th grade project, she had a number of potential projects in mind and used the Ask an Expert forums to talk over her ideas with Experts, including Donna, a process that helped her better understand the demands and feasibility (in terms of timing, concept, and materials) of each project.

For Naima, finding the right project took time, but getting feedback from Experts helped her continue to refine and redirect her energies and interests. "I hear stories about other students who are naturally curious about a particular subject and do a science fair project about that subject. That sounds incredibly simple, but in reality that never happened to me," admits Naima. "I had to dig in to explore my own passion."

The 'aha' moment did happen, however. After researching cellulosic ethanol, Naima says she immediately thought about newspapers. She asked herself, "can I create ethanol from newspaper waste?" Her background research showed that newspapers had been tested for cellulosic ethanol production, but Naima was interested in what affect pretreatment might have.

Building upon her interest in cellulosic ethanol and assimilating Donna's advice into her project design, Naima narrowed down her focus and began working on her 8th grade project, "The NEWspaper Fuel: Enhancing Cellulosic Ethanol Production." The project explored the process of pretreating newspaper to create ethanol (a biofuel). Her experiment tested two different pretreatment methods, one using ethylene glycol (the organosolv process pretreatment method) and one using hydrogen peroxide (the oxidative delignification pretreatment method), to evaluate the effectiveness of each compared to newspapers that have not been pretreated.

A Mentor's Assistance

According to Naima, one of the biggest challenges in creating the experimental design for her project was the heavy reliance on chemistry, a subject to which, as an 8th grader, she had limited previous exposure. Donna, a long-time volunteer at Ask an Expert, helped Naima work through areas of confusion, served as a guide while Naima shaped her experimental design, and helped Naima procure background and research materials to further shape and inform her research.

"It was a great pleasure to be a mentor for Naima on her 8th grade science fair project," says Donna. "I had also advised her on her 7th grade project, a microbial fuel cell project. For her 8th grade project, which was a study on the feasibility of producing cellulosic ethanol using various pretreatment methods to delignify newspaper, Naima took the time to read and understand the scientific literature on her subject. This required learning advanced chemistry concepts but gave her the background she needed to develop a unique project idea."

"There was a lot of chemistry involved," agrees Naima. "All of the quantities and steps had to be very accurate, and that's where reading scientific papers and discussing [them] with Donna helped drastically. It took me three trials to finalize the experimental procedure, but in the end I learned a lot of neat chemistry!"

With Donna's help at Ask an Expert, Naima developed advanced chemical procedures for treating newspapers, procedures that had not been tested before. "She did an outstanding job of designing an experiment with the resources that she had available using homemade equipment and culture media," says Donna.

From Start to Finish

With her experimental design in place, and the project was underway, Naima continued to exchange information with Donna, checking in at each stage of the project, sharing results, and asking questions. The mentorship that developed on the Ask an Expert forums was inspiring to watch unfold. Spanning a period of approximately six months, the "thread" at Ask an Expert on Naima's project contains more than 175 posts.

From Naima's perspective, completing the project without Donna's assistance would have been much more difficult, in part because to successfully work on her project, she had to find ways to approach testing close to home. "I do not live in a university town, and I did not have the opportunity to work in a laboratory or interact with professors," says Naima.

Resounding Success

After all the testing, it was time to analyze her data and results. For Naima, this was not only a challenging aspect of the project but one of the most rewarding. "Offering a glimpse into the scientist she is becoming, Naima recalls, fondly, "the point where I lean back on my chair and look at the final graphs on my computer screen. I have interpreted and analyzed the data, and it all makes sense now. At this point, I have obtained meaningful conclusions which I can relate to potential applications. The conclusions link right back my goal—I have attempted to aid our planet in my own way!"

In the end, Naima's diligent research and hard work was recognized. At her regional fair, Naima won seven awards, including the "Best in Division - Junior" award. She moved on to the Canada Wide Science Fair, where she won a Gold Medal, in addition to a University of Western Ontario Entrance Scholarship, "Energy Challenge - Junior" Award, and the "Renewable Energy - Junior" Award.

A Scientific Journey Unfolds

From its early roots in the desalination project, Naima's interest in environmental science has continued to deepen and evolve. This year, Naima is continuing her work, extending her research into biofuels and adding to the mix of scientific fields one of her favorites, microbiology. While she doesn't plan on working directly in the field of environmental science, she hopes to continue to explore her interest in environmental science through biology. Naima's got the big picture in mind: "I want my research to affect others positively, and contribute towards saving our planet."

The Science Buddies Ask an Expert forums are staffed by volunteer Experts like Donna Hardy from Bio-Rad. Individuals interested in volunteering with Science Buddies can find out more on our volunteer pages. Bio-Rad sponsors the Biotechnology Techniques Interest Area at Science Buddies.

Visitors to Scientific American'sBring Science Home section are treated to an exciting array of activities that encourage families to explore hands-on science. Thanks to an ongoing content partnership between Science Buddies and Scientific American, many of these activities have been created by Science Buddies as fast, family-friendly guided explorations based on our longer science Project Ideas for students.

A Focus on Family Science

Scientific American first launched Bring Science Home in May 2011 as a series of daily activities, a month-long celebration of family science. In response to the overwhelming success of the series, Scientific American began expanding Bring Science Home in October 2011 with new installments added each week.

Every Thursday, Bring Science Home offers a new family-centered science idea, replete with accessible introductory and explanatory material and a guided, hands-on experiment. With topics ranging from pigmentation in fall leaves to whale blubber to static electricity, the activities posted at Bring Science Home take core science concepts and package them for parents in activities that are easy to follow, fun, and use common household materials, natural objects (e.g., leaves), or even toys. Some of these activities are classic experiments that can help users understand important science principles. Concocting a stretchable substance like Silly Putty, for example, offers a perfect—and tactile—look at polymers. Plus, you can have fun testing the putty on the Sunday comics! Similarly, using cabbage to make an indicator solution with which you can test the pH of liquids around the house makes learning about acids and bases a fun and colorful experience—although maybe a bit smelly!

Whether parents are looking to incorporate more science into their family's routine days, or whether they are looking for accessible explanations that can help them talk about and explore science questions that arise (e.g., "Why did my hair crackle when I pulled off my sweater today?"), Bring Science Home invites parents to dive in and investigate science with their families—and to have fun doing so.

"As a kid, I often spent an afternoon after a big rain storm with my brothers tromping down to a local drainage stream to see what the water had washed in," wrote Katherine Harmon, associate editor for Scientific American, in her introduction to Bring Science Home last spring. "And it wasn't unusual to find us sitting around the kitchen table with our hands coated in a green, oozy cornstarch-and-water mixture, wondering at its weird properties. My parents aren't scientists or university professors, and my brothers and I didn't think of these diversions as science. But they were—and these simple activities, along with the questions and conversations they prompted, have stuck with me into adulthood."

With quality, hands-on and engaging content from partners like Science Buddies, Bring Science Home makes these kinds of science experiences and adventures easy for families to adopt and incorporate—no previous science experience required!

Informal Science Exploration

Dr. Teisha Rowland, a staff scientist at Science Buddies, has worked on the weekly activities that Science Buddies has contributed to Bring Science Home. For Rowland, the positive impact of home-centered science is far-reaching. "Bringing science home lets students see that science is not just something that is confined to the classroom setting. Instead, science is something they can explore and investigate on their own, outside of school. This helps students and parents see how science is important in their daily lives, and how it's around them all the time."

Each activity Rowland has prepared for Scientific American has origins in a longer Science Buddies Project Idea. Selecting projects from the Science Buddies library of more than 1000 Project Ideas and rewriting them as engaging activities of high interest to families and students ages 6-12 requires creatively rethinking the experiments, especially in terms of time. "The Scientific American activities are created to be quicker and easier to do than the Science Buddies Project Ideas on which they are based," explains Rowland. "This allows busy families to do a science activity without having to do much planning."

Science Around Us

The bottom line: science is everywhere, and science can be fun. Making parents more comfortable with science, however, and with their ability to integrate science at home, is a critical step in the process of increasing science literacy. For Science Buddies, activities selected to be a part of Bring Science Home are specifically chosen because they start where families are—at home—and focus on what families might be doing anyway, whether it's cooking in the kitchen, blowing bubbles in the backyard, taking a nature walk, or playing with certain kinds of toys.

"The Project Ideas selected to be made into Scientific American activities," says Rowland, "are particularly focused on exposing children and their families to tangible science that takes place around them all the time, such as how leaves change color in the fall and how a remote control sends signals to a radio-controlled car. This helps them see how relevant science is to their daily lives."

Turning science into an a la carte experience may make it as easy to explore friction or building design as it is to do an arts and crafts project, something many families routinely do together. When a LEGO tower can become the basis of a science or engineering discussion, the learning can happen even while the bricks are being snapped together and even amid the shrieks that are bound to accompany the tower's collapse.

"Scientific American's Bring Science Home is a forward-looking initiative that address a very real need in the area of K-12 science education today," says Rowland. "Science Buddies is excited to be a part of helping address this need for students and their families."

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Devon won a blue ribbon with her 7th grade science investigation of the relationship between CO2 output and exercise. To read about other inspiring student and teacher science project successes, visit the Science Buddies in Action page!

Science Buddies in Action

Science Buddies' Topic Selection Wizard zeroes in on the perfect project for a student curious about the pulmonary illness affecting her family. While completing her project, this student gained hands-on experience in life sciences and a better understanding of how exercise can keep lungs healthy.

Student's Family Health History Sparks Scientific Exploration

Devon Lejman had an interest in health and life sciences and, thanks to an older brother, knew exactly where to turn when she needed a 7th grade science fair project—Science Buddies!

After feeding her interests to the Topic Selection Wizard, she was excited to see the Effects of Exercise: Changes in Carbon Dioxide Outputhealth and human biology Project Idea among the Wizard's recommendations. This topic interested Devon because her family has been affected by chronic obstructive pulmonary disease, or COPD. As the respiratory system becomes increasingly damaged, people with this disease find it harder and harder to breathe. As Devon explains, "when a person's lungs cannot effectively remove carbon dioxide (CO2) from the body, the CO2 becomes a large buildup, almost like a blockage."

The Effects of Exercise project gave Devon a way to visualize a person's CO2 output. Using a simple, homemade respirometer, Devon was able to evaluate the amount of CO2 in a person's exhalations by seeing how long it took an indicator to change colors (in response to the presence of CO2). After running the experiment on herself, Devon decided to try the experiment on other people as well. "I wanted a wide variety of test subjects, all with different ages, backgrounds, and amounts of weekly exercise," she notes. Devon successfully garnered several participants, ranging from a triathlete to a 60-year-old with a pacemaker!

Once Devon's subjects completed their tests, she enjoyed comparing their outcomes. "It was interesting to see how different the results were, and how age, average activity, and background affected how long it took for measurable amounts of CO2 to be output." She was also glad to see that her hypothesis was correct: she learned that both exercise and being fit increase the efficiency of CO2 output.

With a helpful recommendation from the Topic Selection Wizard, Devon found an exciting science project that gave her insight into her family's health history and the importance of exercise. On top of that, she won her science fair's Health & Medicine award and the overall award for the 7th grade. For Devon, learning more about human biology and exercise physiology through her science project was a win-win!

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Ahhh.... the allure of the marshmallow shooter... I know it captivated my young Maker Faire attendees last spring... I know adult family members who send marshmallow launcher kits, right along with RC helicopters, model rockets, circuit kits, and solar-powered electronics projects. As this video from President Obama's tour of winning Google Science Fair projects shows, there's something innate to the seemingly timeless fascination with what happens when you combine air pressure, marshmallows, and a series of tubing.

For a look back at our quasi-retrospective on Maker Faire (and our questions about the "germs" that might live in an old-fashioned, blow-style, marshmallow shooter), see: Blow: From Marshmallows to Microbes.

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